Fast, Reliable Blown-In Insulation Across Seguin
Most blown-in insulation jobs in Seguin run $1,800-$4,200 for a typical attic, and our crews can usually inspect and quote same-day if you call before noon. We dispatch from our San Antonio office, which puts us on Seguin doorsteps in under 45 minutes during normal scheduling windows. That matters here because Seguin’s split housing stock - pre-1940s limestone and balloon-frame downtown, plus rapid-built tract homes along FM 78 and IH-10 - doesn’t respond to one-size-fits-all insulation specs. We’ve worked both sides of that divide since 2016, and we know the difference between a courthouse-square retrofit and a compressed-fiberglass fix in a 2019 subdivision. Call (830) 243-6352 for a written price before any work starts.
Why Topside Attic Insulation New Braunfels Is Seguin’s Preferred Blown-In Insulation Company
We’ve sealed and insulated more than 9,000 homes since 2016, and a growing share of that work is in Guadalupe County - particularly the older neighborhoods near Seguin’s historic square and the newer developments pushing toward San Antonio. Seguin homeowners leave reviews that mention the same thing: we show up with a written price, we take blower-door readings before and after, and we leave a documented photo record. No voicemail loops - a live person answers calls 24/7, and we text you when your technician is en route. Under Haven Standard: Arrive on schedule, you get a named technician and a text when they are on the way.
Our familiarity with Seguin’s building stock is specific. We know the 1910s limestone two-stories with no attic floor insulation. We know the pier-and-beam homes west of Diversion Lake with open crawl spaces bleeding conditioned air. And we know the IH-10 corridor tract homes where builders hit price points with minimum-code R-30 blown fiberglass that’s already compressed and uneven. That local knowledge changes what we recommend and how we install it.
Our Blown-In Insulation Services in Seguin

Blown-In Cellulose
We install GreenFiber cellulose in Seguin attics where vapor control matters as much as R-value. The Guadalupe River bottom keeps local relative humidity higher than surrounding upland towns, so cellulose here needs proper ventilation baffles and, in some cases, a vapor-retarding membrane on the attic floor side. Our crew was called to a 1910 limestone two-story near the historic courthouse square where the attic floor had never been insulated; we installed GreenFiber cellulose at a deep, even blanket, then added ventilation baffles at the eaves because the low roofline gave us only inches of clearance to work inside. The homeowner immediately noticed the upstairs rooms stopped cooking by mid-afternoon and the AC stopped running nonstop. Cellulose runs $2.00-$2.80 per square foot installed in Seguin, depending on depth and prep work.

Blown-In Fiberglass
We use Owens Corning and Johns Manville blown fiberglass for Seguin attics where the existing insulation is salvageable and the primary problem is compression or uneven distribution. This is common in the FM 78 and IH-10 corridor subdivisions, where rapid-install crews often left thin spots over living spaces. We don’t blow new material over unsealed top plates or can-light penetrations - air sealing comes first, always. Fiberglass top-ups in Seguin typically run $1.50-$2.20 per square foot. Full-depth new installations run higher.

Dense-Pack Wall Insulation
Seguin’s pre-1940s downtown homes - balloon-frame wood construction and native limestone - were built without wall cavity insulation. Blown-in ceiling insulation alone can’t cut the draft-driven heat load in these houses. Dense-pack cellulose, blown at 3.5 pounds per cubic foot into closed wall cavities, slows that air movement without tearing out plaster. We dense-pack walls in historic Seguin homes where the homeowner wants to keep original interior finishes intact. Pricing starts around $3.50 per square foot of wall area and varies with access method.

Blown-In Top-Up
Many Seguin homes, especially the 2000s-2020s production builds, have some attic insulation but not enough. We measure what’s there, identify compressed or thin zones, and blow additional material to bring the assembly up to performance spec. A typical top-up in Seguin runs $1,200-$2,400 for a 1,500-square-foot attic footprint. We document the before-and-after depth with photos and, on applicable jobs, run a blower-door test - a pressurization reading that shows, in one number, how much air your building envelope is losing.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Before
AfterTrusted Brands We Service in Seguin
We source materials from Owens Corning, Johns Manville, Knauf, and GreenFiber - no proprietary product lock-in, so we match the material to the house rather than the other way around. For Seguin homeowners, that means we stock cellulose and fiberglass locally and can usually schedule installation within a few days of your written quote. We don’t push one brand across every job. A limestone home near the courthouse square with no wall insulation gets a different specification than a 2019 tract home off FM 78 with compressed builder-grade fiberglass. The material choice follows the building science, not a sales quota.
Common Blown-In Insulation Problems We See in Seguin Homes

- Compressed blown fiberglass in IH-10 corridor tract homes. Rapid-install crews in the 2000s-2020s production builds often left uneven coverage, with thin spots directly over bedrooms and living rooms. The insulation looks adequate from the attic hatch but fails to perform where it counts.
- Pre-1940s balloon-frame and limestone homes with zero wall cavity insulation. These downtown Seguin houses rely on thick masonry mass for thermal lag, but without interior or exterior insulation upgrades, the walls radiate heat inward for hours after sunset. Ceiling insulation alone doesn’t solve it.
- Pier-and-beam floor decks bleeding conditioned air in west-side neighborhoods. Near Diversion Lake, open crawl spaces under uninsulated floors create a year-round thermal bypass. Whatever R-value gets added overhead is undercut by air leaking downward.
- Moisture absorption in poorly ventilated river-bottom attics. Seguin’s elevated humidity means fiberglass batts and loose cellulose can lose effective R-value if vapor control and ventilation aren’t addressed at the same time as the thermal upgrade.
Pricing for Blown-In Insulation in Seguin, TX
Here’s what most Seguin homeowners pay for blown-in insulation work:
| Service | Typical Range |
|---|---|
| Blown-in cellulose, full attic (new installation) | $2,800-$4,200 |
| Blown-in fiberglass, full attic (new installation) | $2,400-$3,800 |
| Blown-in top-up over existing insulation | $1,200-$2,400 |
| Dense-pack wall insulation | $3.50-$5.00 per sq ft of wall |
| Attic air sealing + insulation package | $3,200-$5,500 |
Your actual price depends on attic square footage, current insulation condition, accessibility, and whether air sealing is needed first. We don’t blow insulation over an unsealed attic floor - that’s Haven Standard policy, not an upsell. Every job begins with a written price and scope before anyone lifts a tool. We also offer a Free Second Opinion on any written estimate from another contractor. Call (830) 243-6352 for your written quote - estimates are free.
We Also Serve Cities Near Seguin

Our crews work throughout the San Antonio metro corridor. If you’re in Seguin or nearby, we cover New Braunfels, Cibolo, Schertz, and Universal City with the same written-price-first protocol and documented photo record. Dispatch and scheduling are coordinated from our San Antonio office; crews serve Seguin locally.
Serving Seguin, TX - Our Local Coverage Area
We’re based in the Seguin area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Blown-In Insulation in Seguin

Yes, if the existing material is compressed, uneven, or installed without air sealing - which we find in most FM 78 and IH-10 corridor homes built between 2005 and 2020. Builder-grade R-30 blown fiberglass often settles to effective R-19 or lower within a few years, especially if the attic floor wasn’t sealed first. We measure what you have, show you the photos, and quote a top-up or replacement with proper prep. Call (830) 243-6352 for an exact assessment - estimates are free.
Yes, when it’s specified correctly. Seguin’s river-bottom humidity means cellulose needs ventilation baffles at the eaves and, in some attics, a vapor-retarding membrane. Fiberglass needs the same air-sealing prep plus adequate exhaust ventilation. We never install blown-in material without addressing the vapor path. Our Blown-In Insulation team will specify the right assembly for your attic condition. Call for a written quote.
It will help the attic and roof assembly significantly, but it won’t solve draft-driven heat gain through uninsulated walls. Limestone mass provides thermal lag, but without wall cavity insulation, the interior still heats up. We typically recommend blown-in cellulose at the attic floor plus dense-pack wall insulation for these Seguin historic homes. The combined approach runs $5,500-$9,000 for a typical two-story. Call for a written scope and price.
Yes. Homes near Diversion Lake with open crawl spaces often lose more conditioned air through the floor deck than through the attic. We install batt or spray-foam floor insulation - depending on access and clearance - after addressing vapor control to prevent wood deterioration in Seguin’s humid crawl spaces. Floor insulation typically runs $2.50-$4.00 per square foot of floor area. Call (830) 243-6352 for an exact quote.
We install GreenFiber cellulose, Owens Corning blown fiberglass, Johns Manville blown fiberglass, and Knauf fiberglass - selected based on your home’s condition, not a sales script. No proprietary lock-in. The material choice is documented in your written scope before work starts. Call for a free estimate with exact specs.
Written by Wes Okafor, Owner at Topside Attic Insulation New Braunfels, serving Seguin since 2016.